ARI in Hotels (Availability, Rates and Inventory)
ARI hotel data is the room availability, rates and inventory (ARI) that a hotel sends to online travel agencies and to channel managers or switches so they can sell its rooms. The three parts cover whether a room can be booked on a date, what it costs, and how many rooms are left to sell (Introduction, OPERA Cloud Distribution User Guide 24.1 (Oracle)) (ARI overview (Google Hotel Center)).
Last updated: November 2026
How ARI hotel updates work
In Google's implementation, an ARI connection is split into three OpenTravel (OTA XML) messages: one for rate amounts per date or per length of stay, one for availability and restrictions by room type and rate plan, and one for the physical count of rooms available to be sold (ARI overview (Google Hotel Center)).
That split separates two words people often use as one. Inventory is the room count. On Booking.com, availability is the portion of that inventory guests can book based on their search criteria (Rates & Availability API Overview (Booking.com Connectivity)).
The availability message also carries the booking rules for each date, such as whether a rate is open that day and the minimum or maximum length of stay (ari avail XML reference (Google Hotel Center)). See rate restrictions for how these rules are set.
Updates travel by push. The property's system sends a message when its pricing data is new or changed, each message merges with the data already pushed, and Google does not query ARI feeds for a specific itinerary (ARI overview (Google Hotel Center)). A property therefore sends the change, such as one closed date or one new rate, and leaves the rest of its calendar as it stands.
Why ARI matters for hotel distribution
Several systems in a property's stack can be the sender, and each connection works the same way in outline. In a central reservation system such as SynXis, ARI upload messages go out to an OTA system as availability and rates change, with room-level inventory in a message of its own (OTA Distribution setup guides (SynXis developer portal)). At least one property management system API offers calls that push and refresh availability, rates and restrictions (ARI (Cloudbeds API reference)). In one channel manager's push connection, traffic runs in both directions: ARI updates go out to the OTA, and bookings made on the OTA come back to the channel manager as reservation information (Direct Connect Demand (Push) introduction (RateGain developer docs)).
The receiving side is built to match. Booking.com's Rates & Availability API is where a connectivity partner sets inventory, pricing and restrictions for a property's rooms (Rates & Availability API Overview (Booking.com Connectivity)).
For a property, the system that sends ARI, and how quickly it sends a change, decides what guests see on each channel.
ARI hotel term compared with Average Rate Index and channel managers
In revenue reporting, the same three letters stand for Average Rate Index, a metric that compares a hotel's average daily rate (ADR) with the average rate of its competitive set (Hotel ARI: What it is and what it reveals about performance (Hospitality Net)).
| ARI (availability, rates and inventory) | Average Rate Index (ARI) | Channel manager | |
|---|---|---|---|
| What it is | The open dates, nightly rates and room counts a property sends to channels | A revenue metric: the hotel's ADR against its comp set's ADR | Software that sends ARI to OTAs and receives bookings |
| Direction | Pushed by the property when values change | Calculated after the fact from reported rates | ARI out, reservations back |
| Who uses it | Distribution and connectivity teams | Revenue managers | Properties selling on several channels |
Frequently asked questions
What is ARI in the hotel industry?
Does ARI also mean Average Rate Index?
How many ARI updates can a channel accept?
Which restrictions travel with ARI?
Related terms
See all termsWhere Jetstream fits
Jetstream builds an AI channel manager that connects a property's systems to the channels where guests book and keeps rooms, rates and availability accurate on each one, managed from one place.